Auto-coded analyte sensors and apparatus, systems, and methods for detecting same

ABSTRACT

In some aspects, an analyte sensor is provided. The analyte sensor has a plurality of fuse members associated therewith. The fuse members may be burned in sequence and the burn values (related to current, voltage, or time) may be used to extract/decode information. The decoded information may include calibration constant, expiration or manufacture date, counterfeiting codes, warnings, etc. Systems and methods for burning and detecting such burn values of the plurality of fuse members and decoding the coded information related to the sensor are provided, as are numerous other aspects.

RELATED APPLICATIONS

The present application claims priority to U.S. Provisional PatentApplication No. 61/413,374 filed Nov. 12, 2010, and entitled “AUTO-CODEDANALYTE SENSORS AND APPARATUS, SYSTEMS, AND METHODS FOR DETECTING SAME”(Attorney Docket No. BHC104020 (BHDD/027/L2), which is herebyincorporated herein by reference in its entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates to an analyte sensor including auto-codedinformation, and apparatus, systems, and methods for reading suchauto-coded information.

BACKGROUND

The monitoring of analyte concentration levels in a bio-fluid (e.g.,blood) may be an important part of health management (testing and/orcontrol). For example, analyte sensors (sometimes referred to as “teststrips”) may be used for the monitoring of a patient's blood analytelevel (e.g., glucose levels). In analyte testing, for example, thepatient may use a portable lancing device that may be a spring-loaded,trigger-releasable device that receives a single-use, disposable lancet.When the lancet is released, it may prick the user's body part toproduce a droplet of blood. That blood droplet may then be transferredto an analyte sensor that may interface with an analyte testing meter,such as a Blood Glucose Meter (BGM), to calculate and display an analytemeasurement reading. Based upon the reading, certain control measuresmay be undertaken by the user.

Accurate analyte detection may therefore be important to ensuredesirable control measures are undertaken. The accuracy of such analytetesting meters may be, at least in part, affected by being correctlycalibrated. Calibration may be desired to account for batch-to-batchvariations in the reagents applied to the analyte sensor. In someinstances, calibration information may be manually entered. However,there is a marked trend towards the inclusion of auto-coding on theanalyte sensor. In analyte testing meters utilizing auto-coding, theanalyte testing meter reads the sensor's calibration informationautomatically, so that the user need not enter any calibration codes orother information. For example, the auto-coding may, in some existingsystems, be accomplished by including multiple electrical contacts inthe analyte meter that interface with multiple electrical contactsprovided on the analyte sensor. The meter and sensor may thencommunicate electronically to obtain the auto-coding calibrationinformation.

In multi-strip systems (e.g., ASSENCIA® BREEZE® or BREEZE® 2 BloodGlucose Meters available from Bayer Healthcare, LLC, the auto-codinginformation may be provided on, and read from, the analyte sensorpackaging. This elimination of manual entry of the calibration codeinformation both simplifies the management of the disease for the user,and minimizes any risk of improper manual entry that may affect anaccuracy or precision of the analyte detection. However, it may bedesirable to allow more simple access to the encoded information, and/orallow more information to be encoded.

It would, therefore, be beneficial to provide analyte sensors,apparatus, systems, and methods that exhibit improved auto-codingcapability in terms of simplicity and/or amounts of information that maybe encoded.

SUMMARY

In a first aspect, the present invention provides an analyte sensor. Theanalyte sensor includes a sensor body; first and second electrodescoupled to the body; an active region applied in contact with theelectrodes; and two or more fuse members associated with the analytesensor, the two or more fuse members configured to include codedinformation concerning the analyte sensor.

According to another aspect, the present invention provides an analytetesting meter adapted to detect auto-coded information concerning theanalyte sensor. The analyte testing meter includes first and secondelectrical contacts adapted to interface with the analyte sensor, theanalyte sensor having a plurality of fuse members associated with theanalyte sensor, each of the fuse members having a burn value; and adetection circuit adapted to determine the burn values of the pluralityof fuse members.

According to another aspect, the present invention provides an analytetesting system, including a port adapted to receive an analyte sensor;an analyte sensor including a plurality of fuse members associatedtherewith; a detection circuit adapted to produce increasing voltagesufficient to sequentially burn the plurality of fuse members anddetermine a burn values consisting of a time value, a voltage value, ora current value for each fuse member; and a processor adapted to receivethe burn values for each fuse member and decode information associatedwith the analyte sensor.

According to another aspect, the present invention provides a method ofobtaining encoded information. The method includes providing an analytesensor having a plurality of fuse members associated therewith; andburning the plurality of fuse members to provide decodable informationconcerning the analyte sensor.

In another method aspect, the present invention provides a method ofmanufacturing an analyte sensor, including providing a base; formingfirst and second electrodes on the base; applying an active region incontact with the first and second electrodes; and forming a plurality offuse members on the analyte sensor, the fuse members containing coding.

In another aspect, the present invention provides an analyte sensorpackage. The analyte sensor package includes a sealed body containing aplurality of analyte sensors; and a fuse matrix on the sealed bodyconfigured to include coded information concerning the analyte sensors.

In another aspect, the present invention provides an analyte sensorincluding a sensor body; first and second electrodes coupled to thebody; an active region applied in contact with the electrodes; and afuse member associated with the analyte sensor and configured to includecoded information concerning a calibration constant of the analytesensor.

Other features and aspects of the present invention will become morefully apparent from the following detailed description, the appendedclaims and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a top plan view of an example embodiment of an analyte sensorincluding a plurality of fuse members provided according to the presentinvention.

FIG. 1B is a cross-sectional side view of the analyte sensor of FIG. 1Ataken along section line “1B-1B.”

FIG. 1C is a top plan view of another example embodiment of a pluralityof fuse members (shown in isolation) provided according to the presentinvention.

FIG. 2A is a partial top view of another example embodiment of ananalyte sensor provided according to the present invention.

FIG. 2B is a partial top view of a representative fuse member of theembodiment of an analyte sensor of FIG. 2A.

FIG. 3A is a partial top view of another example embodiment of ananalyte sensor provided according to the present invention.

FIG. 3B is a partial top view of a fuse member of the embodiment of ananalyte sensor of FIG. 3A.

FIG. 4A is a partial top view of another example embodiment of ananalyte sensor including a fuse matrix provided according to the presentinvention.

FIG. 4B is an enlarged top view of the fuse matrix utilized in theanalyte sensor of FIG. 4A.

FIG. 5A is a partial top view of another example embodiment of ananalyte sensor provided according to the present invention.

FIG. 5B is a partial cross-sectional side view of the example embodimentof the analyte sensor of FIG. 5A taken along section line “5B-5B.”

FIG. 6 is a partial top view of another example embodiment of an analytesensor including multiple fuse matrices provided according to thepresent invention.

FIG. 7A is a block diagram of an analyte testing meter includingdetection circuitry according to embodiments of the present invention.

FIG. 7B is a diagram of the analyte testing meter including a detaileddetection circuit according to embodiments of the present invention.

FIG. 7C is a graphical plot of a detected voltage (mV) vs. time (sec) ofthe detection circuit according to embodiments of the present invention.

FIG. 8 is a partial top view of another example embodiment of an analytesensor including a fuse matrix provided according to the presentinvention.

FIG. 9A is a partial top view of an example embodiment of an analytesensor package including a fuse matrix provided according to anotheraspect of the present invention.

FIG. 9B is a top view of an example embodiment of a fuse matrix of FIG.9A coupled to a detection circuit according to another aspect of thepresent invention with the package removed for clarity.

FIG. 10 is a flowchart of a method of using the analyte sensor accordingto embodiments of the present invention.

FIG. 11 is a flowchart of a method of manufacturing the analyte sensoraccording to embodiments of the present invention.

DETAILED DESCRIPTION

The present invention, according to a first aspect, provides an analytesensor including associated auto-coded information. The associatedauto-coded information is automatically obtained when the analyte sensoror the packaging/cartridge is inserted into and communicates with ananalyte testing meter. Therefore, the coded information does not need tobe entered by the user. An example analyte sensor according to an aspectof the invention includes a body, and a plurality of fuse membersassociated with the analyte sensor that are adapted to contain theauto-coded information about the analyte sensor. The auto-codedinformation may include detailed calibration information (e.g., acalibration constant) about the analyte sensor, and/or other informationrelated to the analyte sensor. In particular, the auto-coded informationis contained on a plurality of fuses. Each fuse may be burnt (e.g.,blown) by administering a suitable current and/or voltage thereto. Thenumber of fuse members may include two or more, three or more, or fouror more, for example. Each of the fuse members may include a differentburn value (e.g., a current, applied voltage potential, or time) atwhich the fuse member will be burnt. A detection circuit of the analytetesting meter is adapted to sequentially burn each of the fuse membersand record a burn value there for. These representative burn values maybe resolvable into integers adapted to represent coded information. Theintegers may then used to extract associated auto-coded information. Forexample, each burn value may be associated with a stored constant orpiece of information stored in memory of the analyte testing meter(e.g., in a look-up table).

In some embodiments, the analyte sensor may include a body, first andsecond electrodes formed on the body, and a plurality of fuse memberselectrically coupled between the first and second electrodes. Thus, foreach sensor including 2 fuse members, many integer pieces of informationmay be discernable. For example, if the first fuse member has fivepossible fuse burn options and the second fuse member has five fuse burnoptions, then 25 separate coded integers may be provided. As should berecognized, using only a small number of fuse members may allow thecoding of a vast amount of information. In some embodiments, the fusemembers may be included within a fuse matrix to be described more fullyherein below. Of course, the finer the burn increments that may bedesigned and discerned upon burning the fuse member (e.g., every 10 mV),the greater the amount of coded information that may be provided.

In yet another aspect, the present invention provides an analyte testingmeter apparatus and system. The apparatus and system includes adetection circuit that is adapted to burn the plurality of fuse membersassociated with the analyte sensor(s), determine associated burn values,and then decode the auto-coded information associated with an analytesensor(s). This information concerning the burn values may be processedand decoded to generate a calibration constant, for example, such as bycorrelating one or more burn values with a look-up table. In someembodiments, the auto-coded information may be adapted to convey otherrelevant information to a user. Further, the encoded information may beused by the analyte meter solely for internal calculations made thereby.

Auto-coded information that may be provided by the plurality of fusemembers may be indicative of at least two pieces of information selectedfrom a group consisting of calibration constant, manufacturing facility,sales territory, expiration date, manufacturing date, prize winnerinformation, inspirational information, instructional information,anti-counterfeiting information, temperature dependent calibrationcodes, and a unique lot identifying number. The unique lot identifyingnumber may assist the analyte testing meter in recording the number oftests performed from different lots. The unique lot identifying numbermay be used for uploading along with the analyte sensor testing data toa software package for further analysis. This lot number information maybe used by customer support for assisting the diagnosis of user oranalyte testing meter errors, and/or by marketing to study the testinghabits of customers.

In a further aspect, embodiments of the present invention are directedat methods of providing information to an analyte meter. One methodincludes providing an analyte sensor including a plurality of fusemembers associated therewith, sequentially burning the fuse members, anddetermining the burn values for each fuse member. Thereafter, theauto-coded information may be deciphered (decoded) and used incalculations carried out by the analyte meter, or used to display orconvey other useful and/or relevant information to the user.

These and other embodiments of analyte sensors, analyte testing meters,apparatus and systems for interfacing with the analyte sensors, andmethods for using and manufacturing analyte sensors including aplurality of fuse members are described below with reference to FIGS.1A-11.

FIGS. 1A-1B illustrate a first example embodiment of an analyte sensor100 provided according to a first aspect of the present invention. Theanalyte sensor 100 may include a body 102 that may include a base 104onto which the other components of the sensor 100 may be formed orreceived. The analyte sensor 100 may include a length of between about15 mm and 35 mm, for example. The analyte sensor 100 may include amaximum width of between about 3 mm and 10 mm, for example. Other lengthand width dimensions may be used.

The base 104 may be manufactured from any suitable insulating material,such as a polymer material, for example. Suitable polymer materials forthe base 104 may include polyvinyl chloride, polycarbonate,polyethylene, dimensionally stable vinyl and acryl polymers, as well aspolymer blends such as a polycarbonate and polyethylene therephthalateblend. Other polymer materials may be used. The polymer may includeflame retardant materials. In some embodiments, polymers havingrelatively lower melting points may be used.

In the depicted embodiment, applied to, or otherwise mounted on, thebase 104 are a first electrode 106 and a second electrode 108. Theelectrodes 106, 108 may be applied by a screen printing technique oranother suitable technique wherein a pattern of a conductive material isprovided on the base 104. For example, in some embodiments, the patternmay be provided by a printing process (screen printing or inkjetprinting) wherein a fine trace of conductive material such as anelectrode ink (e.g., carbon-based ink) may be applied to form anelectrode pattern extending along a longitudinal length of the base 104.Electrode ink including electrochemically-active carbon and silver mayalso be used.

In some embodiments, a conductive electrode material may be applied(e.g., a noble or other conductive metal) and then laser ablation may beused to create a desired electrode pattern upon a base 104 byablating/removing some of the material. In some embodiments, theconductive material (e.g., a noble metal such as gold, platinum,palladium, or the like) may be sputter coated onto the base 104typically through an evaporative process. Other deposition processes maybe used. A mask that defines the sensor electrode pattern may be placedin contact with the sputter-coated surface. The mask substrate can bemade from quartz with chromium typically being used to define thegeometry and pattern of the desired electrodes. Once the mask is inplace over the sputter coated surface, a high intensity laser may bedirected onto the mask. The conductive material that is exposed to thehigh energy radiation from the laser is ablated leaving an exposeduncoated base 104. The conductive coating that has been protected by themask is left unaffected. Thus, the ablation process may define thegeometrical configuration of the electrode pattern of electrodes 106,108.

The electrodes 106, 108 may include first exposed ends 106A, 108A thatare adapted to connect with electrical contacts of an analyte meter(e.g., a suitable analyte meter is depicted in FIG. 7A-7B) so that theanalyte sensor 100 may be in electrical communication with the analytetesting meter 700 so as to communicate one or more electrical signalsthereto. On the other end of the electrodes 106, 108, the electrodepattern may be provided wherein the electrodes 106, 108 extend in closeproximity to each other and may form at least one gap, or even aplurality of gaps, between the electrodes 106, 108.

In the depicted embodiment, the pattern of the first electrode 106includes first electrode member 106B and a second electrode member 106Cformed on a second end of the first electrode 106. The electrode members106B, 106C may extend across a width of the base 104, for example. Thesecond electrode 108 may include a single electrode member 108B formedon its second end. The single electrode member 108B may be received andinterleaved between the first and second electrode members 106B, 106Cthereby forming multiple gaps, for example. Other patterns may be used.The electrode patterns 106, 108, as applied, may be about 20 microns orless thick, for example. Other thickness may be used. Furthermore, otherthin conductive materials may be used for the electrodes, such aselectrically-conductive metal films or strips. Additional patterns forthe two electrodes may be found in U.S. Pat. Nos. 6,841,052; 6,531,040;7,122,110; 7,118,668; and 7,125,481. In some embodiments, additionalelectrodes may be provided for under fill detection, as is known in theart.

Over a top of the electrode members 106B, 106C and 108B, an activeregion 110 may be applied. The active region 110 functions to convert ananalyte (e.g., glucose, etc.) contained in the bio-fluid sample beinganalyzed (measured) stoichiometrically into a chemical speciesmeasurable in terms of the electrical current generated, or otherwisegenerate an electrical current that may be generally proportional to anamount of the analyte present in the bio-fluid sample. The electricalcurrent may be conducted by the electrodes 106, 108 and read by asuitable analyte testing meter (See FIG. 7A-7B) in electrical contacttherewith. The analyte testing meter 700 may provide a reference voltage(e.g., a voltage bias) during the analyte measurement step. The appliedvoltage bias may be about 250 mV or less. Other voltage biases may beused depending upon the materials used.

Prior to applying the active region 110, a dielectric layer (not shown)may be provided overtop of the electrodes 106, 108 and base 104 inregions where it is not desired for the active region 110 to be applied.In essence, this dielectric layer application functions as a mask toconfine the active region 110 to a precisely defined region (area)proximate to the gaps formed between the electrode members 106B and108B, and 106C and 108B, respectively. The dielectric layer may includea UV-cured polymer, such as an acrylate modified polyurethane material,and may have a thickness of about 10 microns, for example. Otherthicknesses and/or types of insulating materials may be used. Theinsulating layer may be applied broadly enough so that it coversrelatively large areas around the active region 110.

A lid 112 may be provided overtop of the base 104. The lid 112 may befused or otherwise adhered to the base 104 by application of heat andpressure, or by the application of the above-mentioned UV-cured polymer,for example. Other means of fastening the lid 112 may be employed, suchas by the use of an adhesive. The lid 112 may be formed, such as bystamping or heat forming, to have a concave space 114 that may extendfrom the end 107 towards the location of the active region 110. Theconcave space 114 may provide a capillary channel into which a bio-fluidmay pass. The concave space 114 may have a length of about 2 mm to 5 mm,a width of about 0.5 mm to 1.5 mm, and a height of about 0.05 mm to 0.25mm, for example. Other dimensions may be used. The lid 112 may bemanufactured from a deformable polymer material, such as polycarbonate,an embossable grade of polyethylenetherephthalate, or a glycol modifiedpolyethylenetherephthalate, for example. Other types of materials may beused. The polyurethane dielectric material may be applied over an areaencompassed by the lid 112 and may aid in sealing the lid 112 to thebase 104. Further details of the structure of the lid 112 and base 104,as well as attachment details may be found in U.S. Pat. No. 5,759,364. Avent 116 in the form of a hole or perforation may be provided at an endof the concave space 114 to improve capillary action and flow of thebio-fluid sample into the concave space 114 from the end 107 whenapplied thereat by the user.

In accordance with a broad aspect of the invention, the analyte sensor100 is associated with a plurality of fuse members (e.g., fuse members109A, 109B, 109C). The fuse members 109A, 109B, 109C may be provided atpositions along the length of the electrodes 106, 108. Each of theplurality of fuse members 109A, 109B, and 109C may extend between thefirst and second electrodes 106, 108. In the depicted embodiment, thefuse members 109A, 109B, 109C may be arranged along the length of theanalyte sensor 100 from a first end 105 to the second end 107. Otherarrangements may be used. The fuse members 109A, 109B, 109C as shown areprovided overtop of the electrodes 106, 108 and in electrical contacttherewith. Three fuse members 109A, 109B, 109C are shown, however, itshould be understood that any plural number of fuse members may be used,such as two or more, three or more, four or more, etc. Other numbers ofthe plurality of fuse members may be used. In some embodiments to bedescribed herein, the fuse members are provided as a fuse matrix (seeFIGS. 4A-6, FIG. 8, and FIG. 9A-9B). In some embodiments, a single fusemember may be used for encoding a calibration constant. An analytesensor including a single fuse member extending between the electrodesis disclosed in U.S. Patent Application No. 61/413,365 entitled“TEMPERATURE SENSING ANALYTE SENSORS, SYSTEMS, AND METHODS OFMANUFACTURING AND USING SAME” filed on Nov. 12, 2010, the disclosure ofwhich is hereby incorporated by reference herein in its entirety. Thissingle fuse member may be used to encode a calibration constant for theanalyte sensor wherein the calibration constant is related to the burnvalue of the fuse member. For a particularly well controlledmanufacturing process, only a small number of burn value options (e.g.,5-10 possible code options) may be needed for auto-coding of thecalibration constant. These codes, as described herein, may beinterfaced with a look up table in order to obtain the calibrationconstant. The burn value of the single fuse member may be based onvoltage, current, time, or bit information.

In the depicted embodiment of FIGS. 1A-1C, the fuse members 109A, 109B,109C are applied to the base 104 of the analyte sensor 100 andrespective ends thereof are coupled in electrical contact with theelectrodes 106, 108 in an electrical parallel orientation. The largerthe number of fuse members that are provided, the larger the amount ofauto-coded information that may be provided on the base 104 andassociated with the analyte sensor 100.

The auto-coded information may concern or be related to features orproperties of the analyte sensor 100 and/or to information that is to berelayed to, or displayed, to the user, or otherwise related toinformation used by the analyte testing meter (e.g., 700). For example,FIGS. 1A and 1B depict three fuse members 109A, 109B, 109C provided inspaced relationship on the top planar surface of the base 104. In someembodiments, the spaced intervals may be equal (e.g., evenly spacedintervals). Further, the fuse members 109A, 109B, 109C may be centeredon a width of the sensor 100, for example. However, optionally, the fusemembers 109A, 109B, 109C may be provided on the underside of the lid 112and electrically connected with the electrodes upon assembly. Adetection circuit 725 shown in FIGS. 7A and 7B may determine the burnvalues for each of the fuse members 109A, 109B, 109C as the analytesensor 100 is inserted into a port 730 (FIG. 7A) of the analyte testingmeter 700.

In the depicted embodiment of FIG. 1A-1B, the fuse members 109A, 109B,109C may be formed by being printed, marked, or painted, such as by aninkjet, lithography, electrographic printing, or a screen printing. Theymay be formed in electrical contact with each of the electrodes 106, 108or electrically connected therewith upon assembly. The fuse members109A, 109B, 109C may be placed in any suitable position on, orassociated with, the body 102, such that they may be burned and burnvalues for each determined by the analyte meter system 700. In thedepicted embodiment of FIGS. 1A and 1B, the fuse members 109A-109C areformed separately from the electrodes 106, 108 and provided inelectrical contact therewith through the forming step or assembly step.Optionally, as is shown in FIG. 1C, the fuse members 109A-109C may beformed integrally with the electrodes 106, 108 and may comprise a samematerial (e.g., a noble metal film such as a gold film) as theelectrodes. As shown in FIG. 1A, each of the fuse members 109A, 109B,109C may be received in a slight pocket or cavity formed between thebase 104 and lid 112. The pocket or cavity provides a space for anygases formed during fuse burning to expand into.

Each of the fuse members 109A, 109B, and 109C may include a predefinedburn value. The burn value may be a current value, voltage value, ortime value at which the fuse will burn (fail). Each fuse burn value foreach fuse member 109A, 109B, and 109C may be different. For example, ifa voltage is applied, the burn value may be associated with a value ofvoltage at fuse failure. Fuse failure is defined herein as a conditionwhere the fuse melts sufficiently so that no electrical conduction pathis left through the individual fuse member. In other embodiments, theburn value may be related to the maximum current at fuse failure. In yetfurther embodiments, the burn value may be associated with a time (inseconds) at which the individual fuse member fails, as measured from astart time. The fuse burning step may be accomplished by applying aknown input ramp (e.g., a current or voltage ramp as shown in FIG. 7C).The burn value of voltage, current, or time may be stored in memory andused as an input to a routine that uses or correlates that burn value tospecific information or data in a lookup table, for example.

Another embodiment of analyte sensor 200 is described with reference toFIGS. 2A and 2B. This embodiment is similar to the previous embodiment,except that the fuse members 209A, 209B, 209C are provided underneaththe electrodes 206, 208. For example, the fuse members 209A, 209B, 209Cmay be made from a noble metal or other conductive metal and theelectrodes 206, 208 may be later applied as a carbon-based material(e.g., a carbon-based fusible ink). As shown in FIG. 2B, each fusemember (e.g., 209A) may include a fuse region FR that is a region ofreduced dimension as compared to other parts of the fuse member (e.g.,209A). For example, the fuse region FR may include a notch, groove, orother geometrical feature concentrating resistive heating during fuseburning and causing the fuse member (e.g., 209A) to burn at the fuseregion FR. In the FIG. 2A embodiment, each of the fuse members 209A,209B, 209C have substantially the same fuse body thickness and fuse bodywidth of the body, but the fuse regions FR in each have different notchdepths thereby resulting in different fuse region widths W, and thusdifferent burn values for each. Accordingly, the fuse region widths Wmay be used to design and predefine the burn values for each fuse memberand to encode information therein.

Another embodiment of analyte sensor 300 is described with reference toFIGS. 3A and 3B. This embodiment is similar to the previous embodiment,in that the fuse members 309A, 309B, 309C are provided underneath andelectrically connected between electrodes 206, 208. Contrarily, each ofthe fuse members 309A, 309B, 309C have a substantially same fuse regionwidth W (FIG. 3B), but each has a different effective fuse body length L(FIG. 3B). Accordingly, each fuse member 309A, 309B, 309C may have adifferent designed and predefined burn value that is dependent on thefuse body length L (shown dotted). Longer lengths L at the same notchwidth W may exhibit relatively higher burn values (e.g., burn voltages).

Another embodiment of analyte sensor 400 is described with reference toFIGS. 4A and 4B. In this embodiment, the fuse members 409A-409G areprovided in the form of a fuse matrix 409M. “Fuse matrix” as used hereinmeans that a plurality of fuse members (e.g., 409A-409G) are included inclose proximity to each other and each fuse member shares at least onecommon connector to an electrode. As shown, two common connectors 411A,411B electrically connect the fuse matrix 409M to the electrodes 406,408, respectively. The individual fuse members 409A-409G may each have adifferent body width and/or fuse region width such that any number ofcombinations of burn values may be provided. The fuse matrix 409M mayinclude any number of plurality of fuses, such as five or more, ten ormore, or fifteen or more, for example. The fuse matrix 409M may beformed as a stand-alone item that may be adhered to the base 404, lid412, or otherwise deposited (e.g., printed by an carbon-based inkjetprocess) overtop of, or otherwise in electrical contact with, theelectrodes 406, 408.

Another embodiment of analyte sensor 500 is described with reference toFIGS. 5A and 5B. In this embodiment, the fuse matrix 509M is connectedto the electrodes 506, 508 as previously described. However, in thisembodiment, each of the fuse members of the fuse matrix 509M includesapproximately a same body width and fuse region width. A thicknessdimension in a normal direction (designated as along axis 513) for oneor more fuse members may be different. The thickness may be uniformalong most or all of a body length of each fuse member, or may becontrolled thickness only on a portion thereof. Thickness of each fusemember of the fuse matrix 409M may be precisely controlled via inkjetprinting with a carbon-based fusible ink, for example. Accordingly, aburn value of each fuse member of the fuse matrix 509M may be designedto a predetermined value. Thicknesses of the fuse members of the fusematrix 509M may be between about 1 microns and about 25 microns. Asbefore, a void or cavity may be provided in the lid 512 in the vicinityof the fuse matrix 509M. A sealant may seal between the lid 512 and base504 such that no portion of the bio-fluid sample may gain entry into thecavity or make contact with the fuse matrix 509M.

Yet another embodiment of analyte sensor 600 is described herein withreference to FIG. 6. In this embodiment, multiple fuse matrices 609M1,609M2 are provided in contact with the electrodes 606, 608. The fusematrices 609M1, 609M2 may be manufactured from any of the constructionspreviously described.

In more detail, for the three-fuse version shown in FIG. 1A-1B, each ofthe fuse members 109A, 109B, 109C may have a predetermined burn valuethat is associated with time (in seconds). Applying a known ramp ofvoltage at a known ramp rate (e.g., 30 mV/sec) across the electrodes106, 108 of the analyte sensor 100 will cause each fuse members 109A,109B, 109C to burn (fail) in a timed sequence. At failure of each fusemember 109A, 109B, 109C, a discontinuity in an output of a detectioncircuit 725 connected to the electrodes 106, 108 may be measured/sensed(See FIG. 7C). By way of example, in the illustrated embodiment of FIG.7A-7C, the three burn values are designed to exhibit burn values of 1,5, and 7 seconds, for the fuse members 109A, 109B, and 109C,respectively. This may provide integers 1, 5, and 7, or a code of 157.These integers or the code may be correlated with a lookup table todecode information concerning the analyte sensor 100. In otherembodiments, these burn values (burn time values) may be used directlyas inputs to an analyte calculation routine.

In some embodiments, a first time reading associated with a burning of afirst fuse member (e.g., fuse member 109A) may correspond to a referencevalue, and a second time reading may correspond to value that may becorrelated to a calibration code to be extracted and utilized by ananalyte testing meter as part of an analyte measurement sequence. Forexample, if the first fuse member fails at a measured value of 33 mV,and it has been determined that the predetermined value should be 1 sec,then the reference may be used to appropriately scale the other burnvalues so that the other values are more accurately determined.

For example, as shown in Table 1 below, several calibration factors areprovided that correspond to burn values of 2-5 for the second fuse 109B.In this manner, a calibration factor may be provided by the burn of asingle fuse member (e.g., fuse member 109B).

TABLE 1 Lookup Table - Burn Values vs. Calibration Factors Time (sec) 23 4 5 Calibration 1.00 .95 .90 0.85 Factor

The third fuse 109C may be reserved for values 6-10 that may be used toauto-code additional information concerning the analyte sensor 100.However, if more accuracy of calibration is desired, then two fusevalues between 2 and 5 may be used as shown in Table 2.

TABLE 2 Lookup Table - Burn Values vs. Calibration Factors CalibrationInteger Factor 12 1.05 13 1.04 14 1.03 15 1.02 23 1.01 24 1.00 25 0.9934 0.98 35 0.97 45 0.96

Large amounts of coded information may be provided concerning theanalyte sensor 100 with a relatively small number of fuse members.

For example, by using ten fuse members with burn values between 25 mVand 250 mV, ten burn values may be obtained. These ten values may beprovided in various combinations and approximately 512 combinations maybe obtained. In some embodiments, each fuse member or lack thereof ateach respective possible burn value may count for either a 1 bit or 0bit piece of information, thus with 10 fuse members in a fuse matrixover the possible range of burn vales, for example, many codingpossibilities are evident using 1 and 0 bits for the ten different burnvalues. For example, as shown in Table 3 below, the first burn value(bit 1—illustrating the presence of a burned fuse member) is used as areference. The second and third possible fuse members are absent at 50mV and 75 mv, and, thus, a 0 bit may be recorded in memory. As can beseen, many possible coding options are available using either a 0 bit or1 bit information for each possible fuse member. The better thediscrimination (higher number of fuse members) that is achievable belowthe voltage bias, the higher number of coded pieces of information thatmay be provided. These encoded bits may be used to interface with alook-up table and extract a stored calibration constant or otherinformation. For example, the first 4 bits may be used for coding acalibration constant, and the other bits may be used for coding otherinformation as discussed herein.

TABLE 3 Lookup Table - Burn Values vs. Bits BURN Value 25 mV 50 mV 75 mV100 mV 125 mV 150 mV 175 mV 200 mV 225 mV 250 mV Bit 1 0 0 1 0 1 0 1 0 1

These burn values may be determined by an appropriate detection circuit.Detection circuit 725 provided in the analyte testing meter 700 is onesuitable circuit. Other types of circuits may be used. The burn valuesmay be correlated to information or data in a look-up table, stored inmemory, use in calculation(s), or processed and displayed to the user.In some embodiments, a calibration constant may be extracted from one ormore of the burn values and used by the analyte testing meter to affecta proper calibration of the analyte measurement calculation for thatparticular reagent used in that analyte sensor.

In order that the burn values may be easily detectable, it may bedesirable to use only burn values that are separated by a predeterminedamount. In other words, the burn values should be provided that may beappropriately spaced apart from one another by a sufficient margin. Forexample, since the range of voltage used to burn the fuse members shouldbe less than the voltage bias used during the analyte measurement step,the number of fuse members that may be used is roughly based upon thediscrimination over time, i.e., the number of readings that may beburned between 0 and 250 mV. If the burn value of the fuse member may bevery precisely defined and the detection circuit is suitably capable,then as many as 25 fuse members may be used.

In practical application, when an analyte sensor 100 is manufactured,normal manufacturing variations result in differences in the propertiesof the analyte sensors 100 between lots, and even between batches withinlots. Thus, for each batch and/or lot of the analyte sensors produced,there may be a separate calibration constant that may be determined andassigned that will allow an analyte testing meter (e.g., a blood glucosemeter) to adjust its internal analyte value calculation by a calibrationconstant so that an accurate analyte reading is achieved and conveyed tothe user. Such calibration constants may be generated for each batchand/or lot. Once a representative number of the analyte sensors havebeen manufactured and tested, a calibration constant may be assigned forthat lot or batch. Once determined, the appropriate fuse members may beassociated with the analyte sensors in the lot or batch. In someembodiments, after forming the electrodes 106, 108 on the base, a numberof fuse members 109A, 109B, 109C carrying the coded calibrationinformation may be provided overtop and extend between the electrodes asshown in FIG. 1A. Such association may be by printing or otherwiseaffixing the fuse members or a fuse matrix on the body 102 of theanalyte sensor 100. In other embodiments, the fuse members or a fusematrix may be associated with the analyte sensor by being provided onthe packaging for the sensors (e.g., for analyte sensor packagesincluding multiple analyte sensors—See FIG. 9A). This coded informationmay later be extracted and decoded by an analyte testing meter todetermine a calibration constant to be applied in the analytemeasurement calculation carried out by the analyte meter and/orotherwise used to convey other information to the user or the analytetesting meter.

Although embodiments of electrochemical analyte sensors have beendescribed herein as one implementation, it should be recognized that theplurality of fuse members or use of a fuse matrix may be applied to anytype of analyte sensor, such as a photochromic analyte sensor whereby achange of color of a photochromic material onto which the bio-fluid isapplied is measured to detect an analyte concentration level. Likewise,although one application for the analyte sensor of the present inventionis for glucose detection, the present invention may be used for analytesensors for measuring other analytes, such as lactate, keytones, totalcholesterol, uric acid, lipids, triglycerides, high density lipoprotein(HDL), low density lipoprotein (LDL), Hemoglobin A1c, etc.

In some embodiments, the plurality of fuse members may be used todesignate a date of manufacture, or a date of expiration of a particularbatch or lot of analyte sensors 100. For example the use of certaincodes may equate to a particular week of the month. For example, inTable 4 below, various options for week of the month are provided.

TABLE 4 Lookup Table - Burn Values vs. Manufacture Week Integer Week 671st 68 2nd 69 3rd 78 4th 79 5th

Another set of codes may equate to a particular month of the year (e.g.,to a particular year over a period of years), for example.

Additional codes may be used to code additional information such asmanufacturing location, or sales territories into which the analytesensors 100 are intended to be sold. In some embodiments, a code mayalso be used for coding a so-called “golden strip,” which if received bythe user, may reward the user with a prize. For example, if the codedinformation of the fuse members were to equal a predetermined numberstored in memory or in a look-up table upon insertion in an analytemeter, then the user may be rewarded with a free package of sensors oranother prize (such as a diabetes supply organizer).

Furthermore, an anti-counterfeiting code may be included in one or moreof the codes. For example, certain fuse burn values may be used for acertain manufacturing facility but only for certain months of the year.This code could be preprogrammed into the analyte testing meter, and ifthe analyte sensor read by the analyte meter did not include the propercode, the analyte meter would designate a warning or error (displaying“counterfeit strip”) and may instruct the user to return the strip tothe manufacturer of the analyte testing meter for a free replacement,for example. The analyte testing meter may still allow a reading to bedisplayed, but still display a warning that the reading may be suspect.In this way, the manufacturer of the analyte sensor 100 may be readilyplaced on notice of potential counterfeiting activity such thatcorrective measures may be promptly undertaken.

Furthermore, the fuse members may be used to code the correct units ofmeasure (e.g., molarity as expressed by mM/dL, or mass concentration asexpressed by mg/dL, or English or metric units) to be used by theanalyte testing meter.

In some embodiments, inspirational messages may be equated to aparticular code and be displayed on a display of an analyte testingmeter. For example, a saying such as “you are taking good care ofyourself” or “keep up the good work” may be displayed. Further yet,instructional information may be provided by the codes and displayed orotherwise conveyed to the user when a particular code is detected by theanalyte testing meter. All of this useful information may becommunicated between the analyte sensor and the analyte testing meterwith only a relatively small number of fuse members, such as two ormore, three or more, or four or more, five or more, etc.

In accordance with another aspect of the invention, as best shown inFIGS. 7A and 7B, an analyte testing meter 700 is provided. The analytetesting meter 700 includes conventional components, such as processor705, memory 710, display 715 (e.g., a liquid-crystal display or thelike), user interface 720 (e.g., push buttons, keys, a scroll wheel orball, touch screens, or any combination thereof), power source 722(e.g., a 3.0 V power source), power management 723, device interface724, and electrical contacts 726. The processor 705 may be any suitableprocessor. For example, the processor 705 may be any device orcollection of devices that are capable of receiving the signals andexecuting any number of programmed instructions, and may be amicrocontroller, microprocessor, digital signal processor, or the like.For example, a suitable processor is a Cortex M3 equipped microprocessoravailable from ST Microelectronics or Energy Micro. Data received and/orprocessed by the processor 705 may be stored in memory 710, which mayinclude software routines that may be adapted to process the analytedata and determine analyte measurement values, and carryout a fuseburning sequence.

In operation, as an analyte sensor 100 including a plurality of fusemembers 109A-109C is inserted into a port 730 of the analyte testingmeter 700 and contact is made between the electrodes 106, 108 and theelectrical contacts 726 (one contacting each electrode 106, 108), themicroprocessor 705 (e.g., a System On Chip (SOC)) may be awakened. Thismay be provided by a resistance measuring circuit in the Analytemeasurement circuit 745, for example. A routine in software then causesa switch 735 to engage the detection circuit 725 to enable execution ofa checking and/or fuse burning sequence. The switch 735 may be anysuitable switch, such as a multiplexor.

The detection circuit 725, as best shown in FIG. 7B, functions toprovide a changing voltage across the electrodes 106, 108 of the analytesensor 100. In particular, the changing voltage may be caused by aramped voltage input (V_(DAC)) being provided to an amplifier 740. Adigital signal from the processor 705 may be converted in D/A converter742 to provide the ramped voltage input. As each fuse member 109A-109Cis burnt in sequence due to the preferably linearly increasing voltageapplied across the electrodes 106, 108. A tap 743 of the detectioncircuit 725 may measure a voltage output (Vout). The Vout signal mayinclude a perturbation or discontinuity that is produced by the burning(failure) of each fuse member 109A, 109B, 109C, each of which isdetectable.

For example, as shown in FIG. 7C, the first fuse member 109A mayburn/fail at time equal to one second, and fuse 109B may burn/fail at ahigher voltage potential at five seconds, for example. The third fusemember 109C may burn/fail at yet a higher voltage value at time equals 7seconds. The Vout signal of tap 743 may be further conditioned viaoptional amplifier 748 (if needed), and A/D converter 750. An outputsignal in line 751 may be provided to the processor 705 in digitalformat, for example. The time burn values of 1, 5, 7 may be used todecode information, by correlating the time burn values with informationstored in a lookup table stored in memory 710, for example. Optionally,the raw voltage values may be used to measure the burn values. Suchvoltage values (burn values) may be correlated with stored informationto decode the values. Optionally, measured current or time may be usedas the burn values by including a current sensor in the circuit 725.

To determine the burn values, a software routine may execute a slopechecking algorithm that may examine the slope of the representative Voutsignal in line 751. Following initialization, when a slope is detectedthat is above a preset threshold value, a time value may be recorded.Each time value represents an encoded piece of information. That timevalue may be related to the burn value of the respective fuse beingburned at that instant. Optionally, voltage or current at fuse burn maybe used. These respective burn values may be stored in memory,correlated with a look-up table, and use to extract coded informationconcerning the analyte sensor 100.

As discussed previously, the first fuse member 109A may be designed tohave a burn value of one second. A simple error checking routine mayinspect the detected signal Vout in line 751, and if no perturbation issensed by a preset threshold time (e.g., 1.5 seconds), then the routinemay indicate an error. The analyte meter 700 may then output an errorcode, warning, or message to the user via display 715 indicating thatthe sensor 100 is used (fuse already burned) or that the sensor isotherwise “defective.”

As shown in FIG. 7C, the Vout ramp may continue to a preset voltagevalue (e.g., at 250 mV) and then return to zero. At this time, switch735 may be thrown, a suitable voltage bias may be provided across theelectrodes 106, 108 that is above the maximum burn value (e.g., about300 mV), and then the analyte measurement circuit 745 may obtain a rawanalyte measurement value. That raw value may be provided to theprocessor 705. Some of the coded information that was decoded in theprevious step may include a calibration constant. That calibrationconstant may account for batch-to-batch or lot-to-lot variations in theactive region 120. This calibration constant may be used by theprocessor 705 to adjust the raw analyte value to provide a finalmeasured analyte value that may be stored in memory 710, displayed tothe user on display 715, and/or transferred to another system (e.g., adesktop or laptop personal computer (PCs), hand-held or pocket personalcomputer (HPC), compatible personal digital assistant (PDA), and smartcellular phones) or conveyed to a third party via device interface 724.

The processor 705 may centrally manage communications with the othersystem components, such as the display 715, user interface 724, powermanagement 723, and device interface 724. The processor 705 may alsoexecute instructions and sequences in software routines that may handlethe processing of the raw data from the analyte sensor 100 as well asprocessing and decoding information received from the detection circuit725.

The device interface 724 may be any suitable Input/Output (I/O) devicefor allowing data communication with the processor 705 of the analytetesting meter 700, such as wired and/or wireless communications. Wiredcommunications include, for example, communications by universal serialbus (USB) connection. Wireless communications include, for example,radio-frequency (RF) links (e.g., a short-range RF telemetry), infrared(IR) links, and/or Wi-Fi. Some known RF technologies, for example,include Bluetooth® wireless technologies, Zigbee, Z-Sense™ technology,FitLinnx BodyLAN™ system. It should be understood that othercommunication interface technologies, or protocols, may be employed.

Additional embodiments of the invention are described with reference toFIG. 8 and FIGS. 9A and 9B. In FIG. 8, a fuse matrix 809M including aplurality of fuse members is associated with the analyte sensor 800. Inthis embodiment, the plurality of fuse members may be coupled directlyto a second set of electrical contacts 844, 846. Again coded informationmay be provided concerning the analyte sensor 800 by sequentiallyburning the fuse members and determining burn values for some or all ofthe fuse members of the fuse matrix 809M. In particular, a decodingcircuit like detection circuit 725 may be electrically coupled to thecontacts 844, 846 upon insertion of the sensor 800 into an analytetesting meter to carry out extraction of the burn values. A processormay then execute routine to decode information (e.g., calibrationconstants, etc.) associated with the codes. Electrodes 806, 808 areelectrically connected to an active region (not shown, but same as shownin FIG. 1A) and used to obtain the conventional analyte measurement. Asdiscussed before, the matrix 809M may be received adjacent to a sealedcavity 855 (shown dotted) formed in the lid 812, for example. The cavity855 may function as an expansion zone for gases during fuse burning.

As shown in FIGS. 9A and 9B the use of a plurality of fuse members in afuse matrix 909M may provide auto-coding associated with the analytesensors 100 (only one labeled) contained in analyte sensor package 900.The package 900 may be a foil package or cartridge that may be receivedinside of an analyte testing meter (not shown). This sensor package 900may include a sealed body containing a plurality of identical analytesensors 100 and a fuse matrix 909M located on the sealed body; the fusematrix 909M may include a plurality of fuse members configured toinclude coded information concerning the analyte sensors 100 of thepackage 900.

The sensors 100 may be received in one or more individual pockets 904(only one labeled) arranged in the package 900 and the sensors 100 aresealed therein. For example, the pockets 904 may be one or more sealedpockets adapted to seal each sensor 100 around their peripheries. Thismulti-sensor package 900 is designed in this manner in order to reducethe amount of manual manipulation by the user. The package 900 isinstalled into the analyte testing meter, and the analyte sensors 100may be ejected from the package 900 through a port of the analytetesting meter as needed, for example. In the port, the analyte sensorelectrodes are coupled to the analyte meter so that the user may apply adroplet of a bio-fluid thereto and carry out analyte measurementtesting.

Within each package 900, individual sensors 100 that may be producedfrom a same manufacturing batch or lot may share the same calibrationconstant and/or related information (e.g., manufacture date, factory,expiration date, etc.). This calibration code and/or other relatedinformation may be placed on the fuse matrix 909M on the actual package900 that contains the sensors 100 because the calibration code and otherrelated information is common to, and associated with, each analytesensor 100 in the package 900. The coded information may be encoded onthe fuse matrix 909M and the fuse matrix 909M may be positioned on anoutside of the package 900 at any suitable location that may be accessedby electrical contacts of a suitable multi-sensor testing meter. Theanalyte testing meter may include a detection circuit (like circuit 725)for sequentially burning the fuse members of the matrix 909M aspreviously described herein. Other than the application/addition of afuse matrix 909M, the package 900 may be made of a foil material, andmay be, for example, of the same general construction as described inU.S. Pat. Nos. 5,645,798; 5,738,244; and 5,856,195.

The use matrix 909M may be positioned on either side of the container900, and may be arranged in any suitable location and/or orientation.For example, as shown in FIG. 9B, the fuse matrix 909M (shown with thebody of the package removed for clarity) may be arranged on a front orback surface of a disc-shaped package 900 at a center thereof.

As shown in FIG. 9B, the fuse matrix 909A includes an inner contact ring906 and an outer contact ring 908. These rings 906, 908 may be contactedby electrical contacts 910, 912 in the analyte testing meter (othercomponents are the same as in FIG. 7A) to couple the fuse matrix 909M toa detection circuit 925. Detection circuit 925 may be the same asdescribed above. Care should be taken in the design of the analytetesting meter to ensure that the package 900 may only be inserted intothe meter in an orientation that permits the reading of the fuse matrix909M.

As shown in FIG. 10, a method 1000 of providing auto-code informationconcerning an analyte sensor is provided. The method 1000 may include,but is not limited to, providing an analyte sensor (e.g., 100, 200, 300,400, 500, 600, 800, 900) having a plurality of fuse members associatedtherewith in 1002, and burning the plurality of fuse members to providedecodable information concerning the analyte sensor in 1004. Theplurality of fuse members may be provided in any suitable form, such asattached between the electrodes as shown in FIGS. 1A, 1C, 2A, 3A, or asa fuse matrix as shown in FIGS. 4A, 5A, 6, 8 and 9A. A detection circuit(e.g., 725, 925) of an analyte testing meter may cause the burning ofeach of the plurality of fuse members in sequence to provide decodableinformation concerning the analyte sensor. The decodable information maycomprise burn values for each of the fuse members. That informationwhich is associated with the analyte sensor (via being on the sensoritself or on the sensor package) may be decoded in 1006. The decodableinformation (e.g., burn values) may be correlated with data orinformation contained in a look up table or otherwise used. Accordingly,a calibration constant and/or other related information may be decodedfrom the plurality of burn values and used in internal analytemeasurement sequence or otherwise used or displayed.

The method 1000 may use at least some of the decoded information in ananalyte measurement calculation. For example, the method 1000 maycalculate an analyte concentration using an analyte measurementalgorithm and use at least some of the decoded information, such as acalibration constant decoded from the encoded information, in thecalculation in 1008. Additional decoded information may be used in thecalculation, such as information on the proper decoded units of measure,manufacture date, expiration date, etc.

As shown in FIG. 11, a method of manufacturing an analyte sensor isprovided. The method 1100 includes providing a base in 1102, formingfirst and second electrodes on the base in 1104, applying an activeregion in contact with the first and second electrodes in 1106; andforming a plurality of fuse members on the analyte sensor in 1108, thefuse members containing encoded information.

The foregoing description discloses only example embodiments of theinvention. Modifications of the above apparatus, system, and methods,which fall within the scope of the invention, will be readily apparentto those of ordinary skill in the art. Accordingly, while the presentinvention has been disclosed in connection with example embodimentsthereof, it should be understood that other embodiments may fall withinthe spirit and scope of the invention, as defined by the followingclaims.

The invention claimed is:
 1. An analyte sensor, comprising: a sensorbody; first and second electrodes coupled to the body; an active regionapplied in contact with the electrodes; and two or more fuse membersassociated with the analyte sensor, the two or more fuse membersconfigured to include coded information concerning the analyte sensor.2. The analyte sensor of claim 1, wherein the two or more fuse membersextend between, and are electrically connected to, the first electrodeand the second electrode.
 3. The analyte sensor of claim 1, wherein thetwo or more fuse members have different burn values.
 4. The analytesensor of claim 1, wherein the two or more fuse members have burn valueshaving a minimum difference of at least 5% from one another.
 5. Theanalyte sensor of claim 1, wherein the two or more fuse members extendbetween the first electrode and second electrodes and are formed of asame material as the electrodes.
 6. The analyte sensor of claim 1,wherein the two or more fuse members extend between the first and secondelectrodes and are formed of a different material than the electrodes.7. The analyte sensor of claim 1 wherein the two or more fuse membersextend between the first and second electrodes and the fuse membersinclude fuse bodies with different body lengths.
 8. The analyte sensorof claim 1 wherein the two or more fuse members extend between the firstand second electrodes and the fuse members include fuse bodies withdifferent body widths.
 8. The analyte sensor of claim 1 wherein the twoor more fuse members extend between the first and second electrodes andthe fuse members include fuse bodies with different body thickness. 9.The analyte sensor of claim 1 wherein the two or more fuse membersextend between the first and second electrodes and include differentwidth fuse regions.
 10. The analyte sensor of claim 1 wherein the two ormore fuse members extend between the first and second electrodes andinclude different thickness fuse regions.
 11. The analyte sensor ofclaim 1 wherein the two or more fuse members are included in a fusematrix.
 12. The analyte sensor of claim 1 wherein the two or more fusemembers include burn values that are indicative of at least two selectedfrom a group consisting of calibration information, manufacturingfacility, sales territory, expiration date, manufacture date, prizewinner information, inspirational information, instructionalinformation, anti-counterfeiting information, temperature dependentcalibration codes, and lot identifying number.
 13. An analyte testingmeter adapted to detect auto-coded information concerning an analytesensor, comprising: first and second electrical contacts adapted tointerface with the analyte sensor, the analyte sensor having a pluralityof fuse members associated with the analyte sensor, each of the fusemembers having a burn value; and a detection circuit adapted todetermine the burn values of the plurality of fuse members.
 14. Theanalyte testing meter of claim 13, comprising electrical contactsadapted to contact a first electrode and a second electrode of theanalyte sensor, wherein the plurality of fuse members coupled betweenthe first and second electrodes.
 15. The analyte testing meter of claim13, wherein the detection circuit measures a voltage value, currentvalue, or time value for each of the fuse members when each fuse memberis burned.
 16. The analyte testing meter of claim 13, wherein thedetection circuit measures a time value for each of the fuse memberswhen each fuse member is burned.
 17. The analyte testing meter of claim13, consisting of two and only two electrical contacts adapted toelectrically contact the analyte sensor.
 18. An analyte testing system,comprising: a port adapted to receive an analyte sensor; a analytesensor including a plurality of fuse members associated therewith; adetection circuit adapted to produce increasing voltage sufficient tosequentially burn the plurality of fuse members and determine a burnvalues consisting of a time value, a voltage value, or a current valuefor each fuse member; and a processor adapted to receive the burn valuesfor each fuse member and decode information associated with the analytesensor.
 19. A method of obtaining encoded information, comprising:providing an analyte sensor having a plurality of fuse membersassociated therewith; and burning the plurality of fuse members toprovide decodable information concerning the analyte sensor.
 20. Amethod of manufacturing an analyte sensor, comprising: providing a base;forming first and second electrodes on the base; applying an activeregion in contact with the first and second electrodes; and forming aplurality of fuse members on the analyte sensor, the fuse memberscontaining coding.
 21. A method of manufacturing of claim 20, whereinthe plurality of fuse members are included in a fuse matrix.
 22. Amethod of manufacturing of claim 20, wherein the forming comprisesforming a fuse body of the fuse members and then machining a fuse regionfor at least some of the fuse members.
 23. An analyte sensor package,comprising: a sealed body containing a plurality of analyte sensors; anda fuse matrix on the sealed body configured to include coded informationconcerning the analyte sensors contained in the analyte sensor package.24. An analyte sensor, comprising: a sensor body; first and secondelectrodes coupled to the body; an active region applied in contact withthe electrodes; and a fuse member associated with the analyte sensor andconfigured to include coded information concerning a calibrationconstant of the analyte sensor.